Usually, a small electronic component having a contact includes a contact integrated type terminal having a contact portion at one end, and a terminal portion at other end. In such constitution, a structure for picking up a signal directly from the contact portion is widely employed. The prior art of electronic component having such contact integrated type terminal is explained in an example of push switch by referring to FIG. 5.
In FIG. 5, a contact integrated type terminal 122 is attached to the bottom of a box-shaped case 121 made of molded resin by insert molding. A fixed contact portion 122A of the contact integrated type terminal 122 is exposed to the outside position of the bottom of the case 121, and a terminal portion 122B is projected outside of the case 121. A fixed contact portion 126A of other contact integrated type terminal 126 is exposed to the middle position of the bottom of the case 121, and a terminal portion 126B is projected outside of the case 121. These fixed contact portions 122A, 126A are disposed to keep a specific distance, and the contact integrated type terminal 122 and other contact integrated type terminal 126 are mutually in an electrically isolated state. From above the opening of the case 121, a dome-shaped movable contact 123, and an operation button 124 are inserted, and a cover 125 to conceal the opening of the case 121 is provided. At this time, the lower outer circumference of the dome-shaped movable contact 123 is put on the fixed contact portion 122A of the contact integrated type terminal 122, and the movable contact 123 and the fixed contact portion 122A of the contact integrated type terminal 122 are mutually in an electrically connected state.
Recently, this assembling process is fully automated from the first step. Generally, a hoop shaped thin metal plate is set in the machine, and is continuously processed from blanking step to inserting step, and the contact integrated type terminal 122 is assembled.
In the push switch, generally, terminals 122B, 126B are inserted into penetration holes formed in a wiring board or the like, and connected and fixed by soldering.
In the contact integrated type terminals 122, 126 of the conventional push switch, however, the contact portions 122A, 126A require plating on the surface side, but do not require plating on the back side. Moreover, a large plate thickness is not needed in the contact portions 122A, 126A. The terminal portions 122B, 126B require a large plate thickness in order to prevent deformation when mounting on the wiring board, and to assure strength after mounting. Still more, when the contact integrated type terminals 122, 126 are manufactured by blanking process by using a hoop shaped metal thin plate, since the fracture section of the metal thin plate is poor in solderability, it was required that both surface and back sides of the metal thin plate be treated with plating of excellent solderability. As a result, using a metal plate having a large plate thickness and plated on both surface and back sides, the contact integrated type terminals 122, 126 were manufactured. Hence, the cost was high.
On the other hand, to cope with such problem, it was also proposed to use a metal plate partially plated on both sides, but in this case the cost was similar to the conventional metal plate plated on both sides, and it was not effective solving means.
It is hence an object of the invention to solve such problems of the prior art, and present an electronic component having a contact integrated type terminal capable of guaranteeing the mechanical strength and solderability of the terminal portion.